Method of and apparatus for separating leaks from tight cans



March 4 1924. 1,485,896

A. R.:THOMPSON METHOD OF AND \PPARATUS FOR SEPARATING LEAKS FROM TIGHT CANS Fi1ed Nov. 'r. 1923 Fig. l

INVENTOR may F. M AM,

m1 WK ATTORNEYS.

Patented PATENT OFFICE.

ALBERT R. THOMPSON, OF SAN JOSE, CALIFORNIA, ASSIGNOR TO ANDERSON-BARN- GROVER MFG. 60., OF SAN JOSE, CALIFORNIA, A CORPORATION OF CALIFORNIA.

METHOD OF AND APPARATUS FOR SEPARATING LEAKS FROM TIGHT CANS.

Application filed November 7, 1923. Serial No. 673,394.

To all whom it may camera.

Be it known that I, ALBERT R. THOMPSON,

a citizen of the United States, residing at San Jose, in the county of Santa Clara and 6 State of California, have invented certain new and useful Improvements in Methods of and Apparatus for Separating Leaks from Tight Cans, of which the following is a specification.

Myinvention relates, in general, to the canning art, and in particular to a method of and apparatus for separating the leaks from the tight cans.

My invention and apparatus, while adapted for the detection and separation of defective cans, known in the art as leaks, from the perfect or tight cansfin which products of any nature are hermetically sealed, are especially applicable to comestible filled cans, in connection with the cooling phase of the treatment, wherein while still under fluid pressure above atmos heric, the temperature of the cans, is reduce prior to their discharge to the outer atmosphere.

By way of example I may mention the sterilizing of milk in hermetically sealed cans, the treatment of which comprises and includes as the final step the coohngof the cans in a chamber in which a fluid pressure above atmospheric is maintained. Another example is the common process of cookin and cooling sealed cans containing any foo or other product, in which the final step is the cooling under pressure above atmospheric. To either of these examples my method and apparatus are particularly applicable and are utilized in connection with the discharge of the cans from the cooling effect.

In cooling, under pressure, product-filled, sealed cans, any leaky can is open to the entrance of the pressure medium, usually air. This has the effect of equalizing the pressure inside and outside the can, and consequently the moment the canis discharged from the cooler, and the pressure thereby relieved from the exterior of the can, the unbalanced internal pressure will at once cause the heads of the can to bulge, and this bulging condition will continue sufficiently long before the escape through the leaks of the excess of interna pressure, to enable the can to be distinguished from the tight cans,

differentiation upon which my invention is based, and which results in the separation of the leaks from the tight cans.

My invention, therefore, consists essentially in auton'iatically segregating the two kinds of cans, previously subjected to a cooling effect under fluid pressure, above atmosheric, according to the difference of endulge upon their release from said effect. It also consists in the successive steps of and means for first subjecting the cans to an external fluid pressure to provide preliminarily for the equalization of the pressure both inside and outside of the leaky cans, and secondarily to provide, upon the release of said pressure from the outside, for the end bulging of said cans, and then automatically separating said end-bulged cans from the cansnot so bulged, the latter being the tight cans.

In the accompanying drawings I show a simple apparatus for separating the leaks from the tight cans according to my method.

It will be understood, however, that the method is not dependent upon nor confined to this apparatus, as other forms may be used adapted for taking advantage of differences in size or shape.

F ig, 1 of the drawings is a side elevation, of the apparatus; partly broken in the upper portion of the can-selecting member.

Fig. 2 is a section on the line 2-2 of Fig. 1.

1 indicates supporting beams. 2 in Fig. 1 is a box or shell constituting a cooling effect. This may be of any suitable nature such for example as is common in the art, in

the so-called cookers and coolers. Through this cooler the cans pass in continuous procession and during their passage they are subjected externally to fluid pressure, above atmospheric said pressure being here shown as suppliedy means of the compressed air connection indicated at 2.

3 is a chute leading from the discharge of the cooler 2.

4 is a can selecting'member mounted for rotation by means of a shaft 5 journaled in boxes 6 and driven by a pulley 7, as seen in Fig. 2. The selecting member 4 comprises s aced disks, the inner opposing faces of whic are 'parallel at their inner zones as shown at 4, and are flared or relatively divergent at their outer zones, as shown at 4". The floor 3' of the chute 3 leads through between the disks, traverses their parallel-walled inner re ion 4 and forms eyond said disks the floor of the lower delivery chute 8.

An upper delivery chute 9 has its floor 9 passing in between the disks in their flaring-walled region 4 and terminates on a line at the base of said region about at the beginning of its upper descending quadrant. 10, in Fig. 1, indicates the cans without distinction, as they pass from the cooler 2 into the chute 3.

10 are the cans which are tight and are -notbulged; while 10" are the cans known as leaks," and which are end-bulged due to the unbalanced pressure as they leave the cooler. The method carried out in this apparatus is as follows. The product filled cans are carried in continuous procession through the cooler 2 and are therein subjected to external pressure above atmospheric. The leaky cans 10" admit the pressure air to their interior and the pressure within and without is thusequalized. The tight cans 10' are not thus affected. As the leaky cans 10 leave the cooler air and are thus relieved from external pressure, theirends will bulge under their internal pressure which is not immediatelyreleased,

since it takes appreciable time for the air to leak out. The tight cans 10 however leave the cooler with non-bulging ends. In Fig. 1 the cans marked 10 shown coming from the cooler 2, may comprise all leaks or all tights or some of both kinds. When a leak 10" reaches the disks of the selecting member 4 it passes into the flaring outer region 4", and on account of its bulging ends, it becomes lightly wedged in said region as seen in Fig. 2 and cannot pass down therein below the functional level of the floor of the upper delivery chute 9,

so that when, by the rotation of the disks,

it reaches said floor it will pass out into the chute, as is shown in Fig. 1.

But when a tight can-10' reaches the disks of the selecting member 4 it will, on account of its non-bulging ends pass freely across the flaring region 4:" of the disks and will continue along the floor 3, across the parallel inner region 4' of the disks and across the opposite side of the flaring region and into. the lower delivery chute, as seen in Fig. 1.

The leaks are thus detected and separated from the tight cans.

I claim 1. The method of separating the leaks from the tight product-filled, sealed cans, comprising exposing the cans in a region under fluid pressure above atmospheric, adapted to equalize the external and internal pressure upon the leaks; discharging the the procession of cans from said cooling.

region, to release the external pressure and cause the leaks to bulge their ends; and passing said procession without interruption through a region in which the cans are automatically segregated according to the difference of their end bulge.

3. An apparatus for separating the leaks from the tight product-filled sealed cans, comprising means for subjecting the cans to external fluid pressure above atmospheric adapted to equalize the external and internal pressure upon the leaks; means for discharging the cans from said pressure means to release the external pressure and cause the leaks to bulge their ends; and means for auton'iatically segregating the cans according to the difference in their end bulge.

4. An apparatus for separating the leaks from the tight product-filled, sealed cans, comprising a cooling box through which the cans are passed in continuous procession and from which they are discharged, said cooling box being under fluid pressure above atmospheric, whereby the internal and external pressure on the leaks while in the box is equalized, and whereby upon their discharge and the release of external pressure said leaks bulge their ends; means coacting with the can ends for automatically dividing the can procession into separate lines distinguished by a difference in their end-bulge; and means for separately delivering, said divided lines.

In testimony whereof I have signed my name to this specification.

ALBERT R. THOMPSON. 

